Group 13 based Lewis acids having three fluorinated aryl substituents are known to be capable of activating transition metal compounds into olefin polymerization catalysts. Trisperfluorophenylborane is demonstrated in EP 0 425 697 and EP 0 520 732 to be capable of abstracting a ligand for cyclopentadienyl derivatives of transition metals while providing a stabilizing, compatible noncoordinating anion. See also, Marks, et al, J. Am. Chem. Soc. 1991, 113, 3623-3625. The term "noncoordinating anion" is now accepted terminology in the field of olefin polymerization, both by coordination or insertion polymerization and carbocationic polymerization. See for example, EP 0 277 004, U.S. Pat. No. 5,198,401, and Baird, Michael C., et al, J. Am. Chem. Soc. 1994, 116, 6435-6436, and U.S. Pat. No. 5,668,324. The noncoordinating anions are described to function as electronic stabilizing cocatalysts, or counterions, for cationic metallocene complexes which are active for olefin polymerization. The term noncoordinating anion as used herein applies both to truly noncoordinating anions and coordinating anions that are at most weakly coordinated to the cationic complex so as to be labile to replacement by olefinically or acetylenically unsaturated monomers at the insertion site. The synthesis of Group 13-based compounds derived from trisperfluorophenylborane are described in EP 0 694 548. These Group 13-based compounds are said to be represented by the formula M(C.sub.6 F.sub.5).sub.3 and are prepared by reacting the trisperfluorophenylborane with dialkyl or trialkyl Group 13-based compounds at a molar ratio of "basically 1:1" so as to avoid mixed products, those including the type represented by the formula M(C.sub.6 F.sub.5).sub.n R.sub.3-n, where n=1 or 2. Utility for the tris-aryl aluminum compounds in Ziegler-Natta olefin polymerization is suggested.
Perfluorophenylaluminum (toluene) has been characterized via X-ray crystallography. See, Hair, G. S., Cowley, A. H., Jones, R. A., McBurnett, B. G.; Voigt, A., J. Am. Chem. Soc., 1999, 121, 4922. Arene coordination to the aluminum complex demonstrates the Lewis acidity of the aluminum center. However, perfluorophenyl-aluminum complexes have been implicated as possible deactivation sources in olefin polymerizations which utilize Trityl.sup.+ B(C.sub.6 F.sub.5).sub.4.sup.- /alkylaluminum combinations to activate the catalysts. See, Bochmann, M.; Sarsfield, M. J.; Organometallics 1998, 17, 5908. Bochmann and Sarsfield have shown that Cp.sub.2 ZrMe.sub.2 reacts with Al(C.sub.6 F.sub.5).sub.3 0.5(toluene) with transfer of the C.sub.6 F.sub.5 -moiety forming metallocene pentafluorophenyl complexes. These complexes were reported having very low activity compared to the corresponding metallocene dimethyl complexes when activated with B(C.sub.6 F.sub.5).sub.3 or Trityl.sup.+ B(C.sub.6 F.sub.5).sub.4.sup.-.
Supported non-coordinating anions derived from trisperfluorophenyl boron are described in U.S. Pat. No. 5,427,991. Trisperfluorophenyl boron is shown to be capable of reacting with coupling groups bound to silica through hydroxyl groups to form support bound anionic activators capable of activating transition metal catalyst compounds by protonation. U.S. Pat. No. 5,643,847 discusses the reaction of Group 13 Lewis acid compounds with metal oxides such as silica and illustrates the reaction of trisperfluorophenyl boron with silanol groups (the hydroxyl groups of silicon) resulting in bound anions capable of protonating transition metal organometallic catalyst compounds to form catalytically active cations counter-balanced by the bound anions.
Immobilized Group IIIA Lewis acid catalysts suitable for carbocationic polymerizations are described in U.S. Pat. No. 5,288,677. These Group IIIA Lewis acids are said to have the general formula R.sub.n MX.sub.3-n where M is a Group IIIA metal, R is a monovalent hydrocarbon radical consisting of C.sub.1 to C.sub.12 alkyl, aryl, alkylaryl, arylalkyl and cycloalkyl radicals, n=0 to 3, and X is halogen. Listed Lewis acids include aluminum trichloride, trialkyl aluminums, and alkylaluminum halides. Immobilization is accomplished by reacting these Lewis acids with hydroxyl, halide, amine, alkoxy, secondary alkyl amine, and other groups, where the groups are structurally incorporated in a polymeric chain. James C.W. Chien, Jour. Poly. Sci.: Pt A: Poly. Chem, Vol. 29, 1603-1607 (1991), describes the olefin polymerization utility of methylalumoxane (MAO) reacted with SiO.sub.2 and zirconocenes and describes a covalent bonding of the aluminum atom to the silica through an oxygen atom in the surface hydroxyl groups of the silica.
In view of the above there is a continuing need for an activating cocatalyst compound that improves the industrial economics and provides a simpler method of synthesis and preparation of suitable activating compounds for ionic catalyst systems. Additionally, improvements in gas phase and slurry polymerization of olefins, where supported catalysts are typically used, are sought to meet the demanding criteria of industrial processes.